Assabet River NWR, formerly referred to as the U.S. Army's Fort Devens Sudbury Training Annex, is a 2,230-acre parcel of land located approximately 25 miles west of Boston, and 4 miles west of the Eastern Massachusetts NWR Complex Headquarters. It is located in portions of the Towns of Hudson, Maynard, Stow and Sudbury and covers approximately 3.5 square miles. The Assabet River NWR consists of two separate pieces of land. The larger northern section is just north of Hudson Road. The southern section is located to the south of Hudson Road. The refuge is comprised of a diverse mixture of pine/hardwood forest, old field, and wetland habitats. On March 26, 2005, the refuge officially opened for wildlife dependent recreation. As of November 13, 2005, there are 10 miles of trails open to the public for wildlife observation. A map of existing trails is available at the kiosk on Hudson Road in Sudbury and at the refuge website. The refuge is also open for hunting and will open for fishing in Spring 2006. Dogs are not allowed on the refuge. The Friends of the Assabet River NWR formed in 2000, nearly a full year prior to the transfer of the U.S. Army's former Fort Devens Sudbury Training Annex to the U.S. Fish and Wildlife Service. Since that time, the Friends Group has provided the refuge invaluable assistance in preparing to open the refuge for wildlife-dependent recreational activities by removing physical safety hazards; conducting biological surveys of vernal pools, raptors, bats, invasive plant species; and conducting numerous public outreach and education programs. For information on becoming part of the Friends of the Assabet River NWR, contact Barbara Volkle at (508) 393-9251 or visit their website www.farnwr.org.

The main refuge entrance is located at 680 Hudson Road in Sudbury, MA, three miles west of the Sudbury Town Center. Once on the refuge the trail is named Winterberry Way and the Visitor Center will be about half a mile from the main entrance.